What is a Disorder of Gut-Brain Interaction (DGBI)
Disorder of Gut-Brain Interaction (DGBI) is a recent term that encompasses dozens of disorders that occur in over 40% of adults and children. DGBI replaced Functional GI Disorders with the publication of Rome IV in 2016 because of the false perception that “functional” is less legitimate than other disorders. The reason for this originated from and is steeped in the influence of dualistic mind-body principles that separate “organic” disorders, attributed by some to be more “real” and functional disorders (i.e., nonstructural disorders), which are often considered psychiatric or undefined.
The Rome Foundation relied on the Delphi decision-making method to develop a new definition that would be considered positive (rather than excluding other diseases), reflective of current scientific knowledge, and non-stigmatizing. The agreed-upon definition is:
Disorders of Gut-Brain Interaction
A group of disorders classified by GI symptoms related to any combination of:
- Motility disturbance
- Visceral hypersensitivity
- Altered mucosal and immune function
- Altered gut microbiota
- Altered central nervous system (CNS) processing
This definition is most consistent with our evolving understanding of multiple pathophysiological processes that, in part or together, determine the symptom features that characterize the Rome classification of disorders. We believe this definition to be understood and readily acceptable to clinicians, academicians, regulatory agencies, the pharmaceutical industry, and patients.
The most commonly diagnosed and recognized DGBI are:
Irritable Bowel Syndrome (IBS with all sub-types IBS-C, IBS-D, IBS-M)
Functional Constipation or Functional Diarrhea
Chronic Nausea Vomiting Syndrome (CNVS) and Cyclic Vomiting Syndrome (CVS)
Want to learn more about the diagnoses and symptoms associated with a DGBI?
Scroll to see our glossary of terms below and learn even more in our new book: Gut Feelings: Disorders of Gut Brain Interactions and the Patient-Provider Relationship
Glossary of Terms Related to DGBI
Abdominophrenic Dyssynergia: Visible distention of the abdomen characterized by an abnormal reflex of the diaphragm and abdominal wall muscles that often, but not always, occurs after eating. It causes the diaphragm to push down and the abdominal rectus muscle to relax, which leads to the distension. This is unrelated to increased abdominal gas.
Abuse: Threats or actions of an emotional, sexual or physical nature in which a power differential exists between the perpetrator and the victim health providers to treat DGBIs or symptoms associated psychosocial distress
Alarm Symptoms: Symptoms such as fever, bleeding, anemia, weight loss or physical findings such as an abdominal mass that cannot be explained by functional gastrointestinal disorders
Altered Mucosal and Immune Function: Changes to the bowel’s mucous membrane and immune response, e.g., “leaky gut”
Anal Fissures: A small tear in the thin, moist tissue that lines the anus that may occur when passing hard or large stool
Anoscopy: Examination of the anus and lower rectum with a rigid tube
Antidepressant: A class of drugs, now called central neuromodulators (see neuromodulators) whose primary effect is correcting neurotransmitter imbalance in the central nervous system principally to treat major depression. Antidepressants are also valuable for treating abdominal pain, nausea and vomiting in DGBI and also affect concomitant anxiety and depression.
Avoidance Restrictive Food Intake Disorder (ARFID): ARFID is a type of eating disorder defined by severely restricting the type or quantity of foods eaten. The restriction is based on lack of interest in eating or the avoidance of foods to prevent sensory disturbances or concern about aversive effects of eating. ARFID can lead to malnourishment but unlike anorexia nervosa ARFID does not involve alteration of body image.
Balloon Expulsion Test: This is a test for dyssynergic defecation. A deflated balloon is placed in the rectum and then inflated to about 2 ounces of fluid to simulate a stool. Then while sitting privately on a commode chair, the patient is asked to expel the balloon within 2 minutes. If this does not occur the test is considered abnormal.
Belching Disorders: The audible escape of air from the esophagus (supragastric) or the stomach (gastric) into the pharynx. This is considered a DGBI when it is excessive and becomes troublesome.
Biliary Pain: Pain that is episodic and located in the upper quadrant or the epigastrium (upper central region) of the abdomen that lasts 30 minutes or longer and is severe enough to interrupt daily activities or lead to an emergency room visit
Biofeedback Treatment: The use of electronic or mechanical devices to provide visual and/or auditory information (feedback) on a biological process to teach an individual to control the biological process. Generalized biofeedback provides information about large muscles of the body to achieve generalized relaxation. Anorectal biofeedback allows the relaxation of the rectal muscles. Pressure sensors or EMG are placed inside the anus and rectum to provide feedback to the patient on muscle activity during simulated defecation.
Biomedical Model: The model of illness and disease in Western medical education and research. It has two assumptions: 1) mind and body are separate (dualism), and 2) illness and disease originate from a single cuse (biomedical reductionism)
Biomedical Reductionism: The concept that all disease can be reduced to a single etiology or biological cause
Biopsychosocial: The concept that illness and disease result from the combined influence of biological, psychosocial and social factors. The brain and the body interact.
Biopsychosocial Model: A model that proposes that illness and disease result from simultaneously interacting systems at the cellular, tissue, organismal, interpersonal and environmental level. It incorporates the biologic aspects of the disorder with the unique psychosocial features of the individual, and it helps explain the variability in symptom expression among individuals having the same biologic condition.
Bloating: A sensation of discomfort or fullness in the abdomen. It may or may not be accompanied by visible abdominal distension.
Calprotectin Test: A stool test used to detect intestinal inflammation. This is a test to screen for inflammatory bowel disease.
Cannabinoid Hyperemesis Syndrome (CHS): Episodes of vomiting similar to cyclic vomiting syndrome (CVS) in their onset, duration, and frequency. These episodes occur after prolonged, excessive cannabis use and stop when cannabis use is discontinued.
Catastrophizing: A type of unhelpful thinking. Catastrophic thoughts tend to dwell on the worst possible outcome of any situation in which there is a possibility of an unpleasant outcome (e.g., a person taking an airplane dwells on the possibility of the airplane crashing).
CBC: Complete Blood Count. This tests for anemia (red cells), inflammation (white cells), and clotting tendency (platelets)
Celiac Disease: A disease that may present similar to IBS but is due to an allergy to gluten, a protein found in wheat, barley and rye. It is treated by reducing gluten in the diet.
Centrally Mediated Abdominal Pain Syndrome (CAPS): Continuous, nearly continuous, or frequently recurrent abdominal pain that is often severe and not or rarely related to changes in gut function such as eating or defecation. The pain is not feigned or related to another gastrointestinal disorder. The chronic and severe pain associated is a hallmark complaint.
Chronic Nausea Vomiting Syndrome: Nausea occurring at least one day a week that is severe enough to impact usual activities, and one or more vomiting episodes a week. However nausea can occur without vomiting. Eating disorders and self-induced vomiting must be excluded, and tests (including an upper endoscopy) find no evidence of organic abnormality.
Coccygodynia: Pain in or around the bony structure called the coccyx at the base of the spine
Cognitive Behavioral Therapy (CBT): Several approaches or sets of techniques used by mental health professionals. CBT focuses on challenging and changing unhelpful cognitive distortions (e.g. thoughts, beliefs, and attitudes) and behaviors, improving emotional regulation, and developing personal coping strategies that target solving current problems. It has been proven successful in treating DGBIs
Colonoscopy: An endoscopic examination of the lining of the colon to find polyps or inflammation
Colon Polyp: An abnormal growth in the colon lining that can develop into a cancer. This more often occurs when there is a tubular adenoma ≥ 10 mm in size, an adenoma of any size with villous features or high grade dysplasia, or a dysplastic serrated lesion of any size.
Co-Morbidity: The simultaneous presence of two chronic diseases or conditions in a patient
C-Reactive Protein Blood Test: A blood test that checks for inflammation in the body
Crohns Disease: A chronic inflammatory bowel disease characterized by inflammation, ulceration of the colon or small intestine, which can be complicated by bleeding, obstruction or infection. This needs to be excluded in patients presenting with functional bowel complaints of pain and diarrhea.
Cyclic Vomiting Syndrome (CVS): A functional gastroduodenal disorder characterized by Intermittent stereotypical episodes of intense nausea and vomiting (up to 30 times a day) that may occur multiple times a year, lasting for a week or more, and the absence of nausea and vomiting between episodes
Defecography: An x-ray or MRI technique that provides a detailed view of the anatomy and functioning of the rectum and pelvic floor before and during attempted defecation
Disorder of Gut-Brain Interaction (DGBI): This was formerly called a Functional GI Disorder. DGBI more appropriately identifies these disorders as dysregulation of the Brain-Gut Axis. Patients with these disorders may have visceral hypersensitivity, altered mucosal immune function, altered microbiota or central dysregulation.
Diverticulitis: The infection or inflammation of the pouches that can form in the colon
Dysphagia: Difficulty swallowing as if the food is stuck or moving slowly but without pain
Dyssynergic Defecation: A functional anorectal disorder caused by Inappropriate or paradoxical contraction of the pelvic floor with failure to relax the levator muscle (puborectalis), associated with straining and difficulty evacuating
Ejection Fraction: Ejection fraction (EF) is a measurement, expressed as a percentage, of how much the gallbladder empties after contracting. An ejection fraction of less than 40% is suggestive of functional gallbladder disorder
Empiric Value: Based on practical experience instead of scientific proof
Enterocele: Descent of loops of small intestine into the pelvis that bulge into the vagina during straining. An enterocele may cause pain, a sensation of fullness and/or obstructed defecation
Eosinophilic Esophagitis (EOE): A chronic, inflammatory disease of the esophagus associated with large numbers of eosinophils in the emucosa. This disorder may be dietary or allergic related.
Eosinophils: A type of inflammatory cell that can be seen in increased numbers in allergies or parasitic infections. It is increased in eosinophilic esophagitis and in certain types of functional dyspepsia.
Epigastric Pain Syndrome (EPS): A subtype of functional dyspepsia characterized by epigastric pain or burning that may or may not occur in relations to meals
Esophageal Spasm: Increased contractions of the esophagus which can be seen by barium swallow x-ray or by esophageal manometry
Etiology: The cause, set of causes, or manner of causation of a disease or condition
Excessive Supragastric Belching (From Esophagus): Excessive belching that occurs more than 3 days a week, caused by gas that originates from air swallowing into the esophagus which is then released
Excessive Gastric Belching (From Stomach): Excessive belching that occurs more than 3 days a week, caused by air swallowing into the stomach which is then released
Fecal Elastase: A stool test to determine if there is pancreatic insufficiency causing diarrhea The pancrease produces elastase so the elastase value is decreased in pancreatic insufficiency
Fecal Incontinence: Recurrent uncontrolled passage of fecal material. It is a DGBI if present for at least 3 months
Feigned: Consciously faked
Fibromyalgia: A chronic disorder characterized by widespread musculoskeletal pain, fatigue, and tenderness in localized areas
Functional Abdominal Bloating/Distension: A functional bowel disorder characterized by recurrent bloating and distension of the abdomen that occurs on average at least 1 day a week and predominates over other symptoms. To make this diagnosis by Rome Criteria, other DGBIs should be excluded.
Functional Anorectal Pain: A functional anorectal disorder characterized by pain in the anorectal area which is distinguished by the duration of pain and the presence or absence of anorectal or levator tenderness.
Functional Biliary Sphincter of Oddi (SO) Disorder: A functional biliary disorder characterized by biliary pain in the absence of bile duct stones or other structural abnormalities associated with abnormal liver enzymes or a dilated bile duct (but not both). Often, the gallbladder has been surgically removed
Functional Chest Pain: A functional esophageal disorder characterized by recurring, unexplained chest pain behind the sternum that is not experienced as heartburn but is believed to be related to the esophagus. Heart disease should be excluded by medical evaluation or cardiac diagnostic studies.
Functional Constipation: A functional bowel disorder characterized by difficult defecation and infrequent or incomplete bowel movements. Abdominal pain or bloating may be present but do not predominate (as they do with IBS-C).
Functional Defecation Disorders (FDD): A functional anorectal disorder that is also called pelvic floor dyssynergia. It is characterized by frequent excessive straining, feeling of incomplete evacuation with defecation, and at times digital facilitation of bowel movements. The pelvic floor muscles contract with defecation, rather than relaxing, as they should, or there is not enough pressure (propulsive force) to defecate.
Functional Diarrhea: A functional bowel disorder characterized by loose or watery stools, without predominant abdominal pain or bothersome bloating, occurring 25% of the time or more. Patients meeting criteria for IBS-D should be excluded
Functional Dyspepsia: A functional gastroduodenal disorder in which any of the following apply: The unpleasant sensation of food staying in the stomach after a meal (“postprandial fullness”); the unpleasant feeling that the stomach is overfilled soon after starting to eat (“early satiety”); subjective, intense pain in the area just above the stomach (“epigastric pain”) and/or unpleasant, subjective sensation of heat in the epigastrium. These symptoms significantly impact usual activities.
Functional Dysphagia: A functional gastroduodenal disorder characterized by a sense of solid and/or liquid foods sticking, lodging, or passing abnormally through the esophagus
Functional Gallbladder Disorder: A functional gallbladder disorder characterized by biliary pain in the absence of gallstones or other structural pathology. It may be diagnosed by a low ejection fraction.
Functional Heartburn: A functional esophageal disorder characterized by burning discomfort or pain (i.e. heartburn) experienced behind the breastbone (retrosternal) that is not associated with increased acid reflux. It does not respond to acid-blocking treatments and is not caused by any structural diagnosis like GERD or a motility disorder.
Functional Pancreatic SO Disorder: A functional Sphincter of Oddi disorder characterized by biliary pain associated with increased pressures in the pancreatic duct leading to inflammation of the pancreas and elevated pancreatic enzymes. These patients may be treated by endoscopic sphincterotomy.
Gastroduodenal Disorders: A class of DGBIs involving symptoms that are attributed to the stomach and the duodenum (the first part of the small intestine, immediately beneath the stomach)
Globus: A functional esophageal disorder characterized by the persistent or intermittent non-painful sensation of a lump or foreign body in the throat. It occurs episodically and is felt in the midline above the sternal notch.
Gut Microbiota: The microorganisms found in the intestines or gut
H Pylori Infection: A type of bacteria that produces inflammation and ulcers in the stomach. This may produce symptoms consistent with functional dyspepsia and if found may be eradicated with antibiotics
Hematochezia: The passage of bright red blood via the anus
Ileus: The loss of normal peristalsis or contractions of the bowel, which can be due to motility disorders such as pseudo-obstruction, after abdominal surgery, or after certain types of medications that slow down motility.
Inadequate Defecatory Propulsion: A type of anorectal disorder characterized by inadequate propulsive force of the rectum preventing proper defecation
Intraluminal Impedance: A type of test usually done with pH (acid) testing to evaluate heartburn. It is based on the measurement of changes in resistance to alternating electrical current when a bolus passes by a pair of metallic rings mounted on a catheter.
Irritable Bowel Syndrome (IBS): A functional bowel disorder characterized by recurrent abdominal pain that is related to defecation and associated with constipation, diarrhea, or a mixture of both; abdominal bloating and distension may also be present. The IBS subtypes C, D, M, and U are differentiated by relative frequencies of the stool form
Levator Ani Syndrome: A type of anorectal disorder characterized by rectal pain that is often described as a vague, dull ache, or a sensation of pressure high in the rectum lasting 30 minutes or longer. It is often worse when sitting than when standing or lying down. Physical examination reveals tenderness when the doctor presses on the pelvic floor (posterior traction of the levator) muscle. Other structural disorders of the pelvic floor must be excluded.
Lipase Test: A blood test that measures a type of protein (lipase) in the blood that is produced by the pancreas. It is a way to diagnose pancreatitis based on elevated blood levels.
Manometry: Anorectal manometric (ARM) measures the anal and rectal pressures and EMG (electromyogram) electrical activity during attempted defecation. When these tests are normal, increased intrarectal pressure is associated with anal relaxation. An abnormal study will demonstrate inappropriately increased pressures or inadequate relaxation of the rectum or the anal sphincter during simulated defecation.
Microbiota: All the microorganisms (bacteria, yeast, fungi, viruses) living in a specific environment, called a microbiome.
Mind-Body Dualism: A concept promoted by René Descartes in the 17th century that promotes the separation of the mind and the body. In Western medicine this has led to a distinction between “organic,” i.e., structural disorders or “functional,” i.e., not structural disorders that are considered less legitimate. It has promoted the misunderstanding of DGBIs as psychiatric or not real and is challenged by the biopsychosocial model.
Motility Disturbance or Dysmotility: Disorders that are characterized by abnormal movement inside the bowels
Narcotic Bowel Syndrome (NBS) / Opioid-Induced GI Hyperalgesia: A centrally mediated disorder of GI pain characterized by the development of (or increases in) abdominal pain associated with continuous or increasing dosages of opioids. Other medical diagnoses do not explain the pain. When opioid use ends, improvement or resolution will occur.
Nausea: Queasiness or sick sensation. It is the unpleasant sensation of needing to vomit, typically felt in the upper abdomen immediately above the stomach or throat.
Nausea And Vomiting Disorder: Chronic nausea and vomiting disorder (CNVS) is a functional gastroduodenal disorder related to chronic nausea, vomiting or both.
Neuroplastic: A characteristic of the plasticity of nerve cells indicating that they can grow (neurogenesis) and shrink (neurodegeneration)
Neuromodulator: A new term reflecting the pharmacological effects of neurotransmitters on the brain-gut axis. They are used to treat DGBI symptoms. Central neuromodulators (e.g., antidepressants, antipsychotics, anti-anxiety agents) primarily affect the central nervous system but also affect the enteric nervous system. Peripheral neuromodulators (e.g., alosetron, linaclotide) act principally on the enteric nervous system
Odynophagia: Painful Swallowing
Opioid-Induced Constipation: When initiating, changing, or increasing opioid therapy, there are new or worsening symptoms of constipation.
Orthorexia: The disordered thought process that certain foods are producing unwanted symptoms or health impairments that lead to food restriction
Pancreaticobiliary Disease: Disorders of the gall bladder, biliary ducts, and pancreas
Pathophysiology: The physiological understanding of how and why medical disorders are occurring
Patient-Doctor Relationship: Ideally understood in terms of interpersonal behaviors that enhance or diminish mutual communication, satisfaction and trust. Positive physician behaviors are characterized by empathy, respect, and positive regard.
Pelvic Floor: The pelvic floor relates to the rectal and urogenital region of the human body. It comprises muscle fibers of the levator ani, the coccygeus muscle, and associated connective tissue that span the area underneath the pelvis. The pelvic floor separates the pelvic cavity above from the perineal region (including perineum) below. Because, to accommodate the birth canal, a female’s pelvic cavity is larger than a male’s, the pelvic floor tends to be considered a part of female anatomy, but males have an equivalent pelvic floor.
Peristalsis: The involuntary constriction and relaxation of the muscles of the intestine or another canal, creating wave-like movements that push the contents forward through the GI tract
Postprandial Distress Syndrome (PDS): A subtype of functional dyspepsia. It is characterized by the uncomfortable sensation of being too full soon after eating a meal or becoming full so early that eating a regular-sized meal is prevented. PDS is characterized exclusively by meal-induced symptoms.
Postural Orthostatic Tachycardia Syndrome (POTS): This is a functional vascular disorder commonly associated with some DGBIs. It relates to an abnormal heart rate or blood pressure increase after sitting up or standing. Some typical symptoms include dizziness and fainting. It is related to abnormal regulation of the autonomic nervous system. POTS may be seen with IBS or other DGBI.
Proctalgia Fugax: This is a functional anorectal disorder characterized by recurrent episodes of pain in the rectal area, lasting for a few seconds to several minutes (up to 30 minutes) and then disappearing completely. The pain is usually localized to the rectum; it has been described as cramping, gnawing, aching, or stabbing; and may range from uncomfortable to unbearable.
Proton Pump Inhibitors: Medications designed to decrease acid secretions. Examples include Prilosec (omeprazole), Nexium (esomeprazole) or Protonix (pantoprazole).
Pseudo-Obstruction: Intestinal pseudo-obstruction is caused by nerve or muscle problems that prevent the intestines from contracting normally to move food, fluid, and air through the intestines. Symptoms may include cramps, abdominal pain, nausea, vomiting, bloating, constipation, and occasionally diarrhea.
Rectal Prolapse: Protrusion of the mucosal lining of the rectum through the anus
Rectoanal Reflex: The rectoanal inhibitory reflex (RAIR) is a reflex characterized by a transient involuntary relaxation of the internal anal sphincter in response to distention of the rectum. When difficulties occur with proper relaxation, we call this dyssynergic defecation.
Rectocele: A weakening of the wall between the rectum and vagina. It can develop from weakness in the wall from multiple vaginal deliveries or surgeries or repeated straining leading to increased abdominal pressure generated that pushes the rectal wall into the vaginal area.
Reflux Hypersensitivity: Heartburn or chest pain when endoscopy and pH studies are normal, but symptoms occur when acid enters the esophagus. This is not GERD because esophageal pH testing shows no increased acid, but the esophagus is found to be sensitive to acid.
Retrosternal: Located behind the breastbone, or sternum
Rome Criteria: Lists of symptoms in which a specified minimum number allows a diagnosis of a DGBI. The criteria change over time depending on scientific investigation. Rome IV are the current criteria.
Rumination Syndrome: A functional gastroduodenal disorder characterized by repetitive, effortless regurgitation of recently eaten food into the mouth, which is then re-swallowed or spit out. Regurgitation is not preceded by retching and occurs before the food has turned into acid.
Sacral Nerve Stimulation: An implant that delivers gentle electrical impulses through a probe (a thin wire) that is placed near the sacral nerve. The technology is similar to a pacemaker, but instead of regulating a person’s heartbeat, it stimulates the bowel, sphincter and bladder muscles to work normally. It is used to treat fecal incontinence.
Satiation: The feeling after eating of being full
Scintigraph: Also known as a gamma scan, this is a diagnostic test in nuclear medicine where radioisotopes attached to drugs that travel to a specific organ or tissue (radiopharmaceuticals) are taken internally, and the emitted gamma radiation is captured by external detectors (gamma cameras) to form two-dimensional images in a similar process to the capture of x-ray images.
Scintigraphic Test: A test to evaluate slow gallbladder emptying (CCK-CS) involving the intravenous administration of technetium 99m (Tc 99m), which is excreted into the biliary tract and concentrated in the GB. The rate to which the Tc 99m empties out of the gallbladder is called the ejection fraction (EF). The diagnosis is supported if the EF is low (usually 40% or less).
Secretagogues: A class of drugs to treat constipation and IBS-C that increase fluid into the intestines to produce a more frequent, softer stool, and to reduce bloating
Sitaphobia: Fear of eating due to unwanted side effects, usually pain
Sitzmarker/Intramarx Test: A sitz marker study is where capsules containing small radio opaque markers are ingested to evaluate how quickly they move through the colon. The capsules are taken daily and after 3 or 5 days, an abdominal x-ray is taken. This test is most often used with patients who are suffering from chronic constipation.
Splinting: A technique where the patient uses a finger to push up and back either at the back of the vagina or in the area between the vagina and rectum (perineum). This straightens the anorectal angle to allow for easier passage of stool. Splinting is commonly used as a treatment for patients who have a rectocele.
Stricture: An abnormal narrowing of a bodily passage (as from inflammation, cancer, or the formation of scar tissue)
Unspecified Functional Anorectal Pain: A type of anorectal disorder characterized by the same symptoms as Levator Ani Syndrome, but upon rectal exam there is no tenderness when the doctor presses on the levator muscle.
Unspecified Functional Bowel Disorder: A type of functional bowel disorder where bowel symptoms, including abdominal pain or change in bowel habits, do not have an organic cause and do not meet criteria for IBS or functional constipation, diarrhea, or abdominal bloating/distention disorders.
Upper Endocosopy: A test in which a thin scope with a camera is used to look inside the esophagus, stomach and duodenum
Vagal Nerve: This is the 10th cranial nerve that carries information between the brain and other organs of the body, including the GI tract, heart, and lung. It is a parasympathetic nerve bringing information from and to the digestive organs.
Vasovagal Reflex: An abnormal reflex that can occur, causing problems like a drop in blood pressure or abdominophrenic dyssynergia; it may relate to increased autonomic reactivity
Visceral Hypersensitivity: One of the main features of IBS and some other DGBIs is increased firing of nerves in the digestive tract after stimulation or stretching of the bowel. This produces a lower pain threshold and explains why patients with DGBI may get pain after eating.
Vomiting: Vomiting is the forceful oral expulsion of gastrointestinal contents associated with contraction of the abdominal and chest wall muscles; it is usually associated with nausea.